What's in a name? In the Bible, plenty!
Names were very important to the ancient Hebrews. To name someone was to have power over that person, and to use the Name of Godde was to use Godde's power.
We see remnants of this even today; parents name their children, and the child has nothing to say about it until he or she becomes an adult. Nicknames adopted after about the age of seven may be an unconscious attempt to break away from parental control. And names even today have some small power over their holders — a boy named Sue (or Shirley, or Dana, or Marion) has to work harder to prove his manhood; at least one girl with a boy's name has gotten drafted.
We learn about the power of names for the ancient Hebrews almost immediately: In the first chapter of Genesis, we learn that "Godde called the light Day, and the darkness he called Night." (1:5). In other words, having created it, Godde has power over light itself!
Similarly, we learn that "Godde called the dome Sky" (1:8) and "God called the dry land Earth, and the waters that were gathered together Godde called Seas" (1:10) — in naming these things, Godde is shown to have dominion over outer space, over the Earth, over everything on the earth.
Moreover, the words translated "Light" and "Sky" and "Earth" and "Water" were the names of powerful gods of other ancient religions. The writer, in other words, is saying that Godde has power even over these lesser beings that some cultures worshipped as gods.
In the second creation story, the power of names is stressed yet again. We learn that Godde used red dirt (the Hebrew word is 'adamah) to create the first human being (the Hebrew word for person, not specifically either male nor female, is also 'adam; the Hebrew word for blood is dam.). When Godde decided that the earth creature needed a companion, God separated it into the man ('ish) and the woman ('ish-shah).
In Genesis 2:19, it says that "whatever the 'adamah called an animal, that was its name" — in other words, Godde has given human beings dominion over all other creatures.
It was not until after the woman and the man had eaten the fruit of the Tree of Knowledge of Good and Evil that they became enough like Godde to be named. Godde named Adam ("the human being") to signify Godde's power over all humanity, and Adam named Eve ("to be alive) as a reflection of men's power over women in ancient Hebrew society.
Godde renamed Abram ("ancestor") to Abraham ("ancestor of a multitude") for a similar reason — not only to show that Godde has power over him, but also to show that, because of Godde's covenant with him, he has become God's particular friend. Godde changes the name of Jacob ("the supplanter" — remember, Jacob conned his brother Esau ("hairy") out of his inheritance) to Israel ("the prince who prevails with God") again to show that Godde claims Jacob, that Godde has dominion over him.
(Incidentally, Godde is not the only one who changes someone else's name. In II Chronicles 36:1-4, Pharaoh Neco of Egypt installs his puppet, Eliakim ("raised up by Godde"), on the throne, changing his name to Jehoiakim ("whom Jehovah sets up") as a sign that he "belongs" to the pharaoh.}
The power of names was considered very real, and highly important. One's name was also a representation of oneself, so to use someone's name was much like using a voodoo doll would be today, if voodoo were real. This is why for thousands of years no one called Godde by any name at all; Godde was referred to only as YHWH, which in the Bible is translated either Yahweh or Jehovah. YHWH is sometimes called the Tetragrammaton ("the four letters").
Here's how important names are: the first commandment is to remember that there is only one Godde in the entire Universe. The second commandment (in Deuteronomy; it's the third commandment in Exodus) is, "You shall not make wrongful use of the name of YHWH your Godde." (Or, more thoroughly, "Don't try to use or take for yourself power that is Godde's alone; you can only fail.")
To blaspheme is to speak contemptuously or mockingly of Godde, and is always a bad thing, but that's not really what this commandment is about. Because a name participates in the power of the person to whom it belongs, making wrongful use of Godde's name means making wrongful use of Godde's power — or trying to, anyway. This commandment covers any attempts to make use of Godde's power, including black magic, astrology, fortune-telling, casting spells and curses ("Drop dead!"), rain-dancing, voodoo, casting the Evil Eyes, and similar activities.
(Incidentally, this commandment does not mean that one cannot make any use of Godde's Name, as for example in swearing oaths. YHWH swears by Godde's own name in the Old Testament, since there is nothing higher by which Godde might swear. When Jesus tells us not to swear at all in Matthew 5:33-37, he is not extending the Third Commandment; rather, he is saying that one's promise should be good enough by itself, without calling on some higher authority to bolster it up.)
Well, but— you say. Before the coming of Jesus, Godde was referred to by a number of names — YHWH, El (male), Eloah (the same word, but female), Elohim (the same word, but plural), El Shaddai (the Godde with female breasts), El Elyon (Godde the wise Godde ), etc.). What about that, hunh? It's simple: by using all these names indiscriminately to refer to the same being, the Bible is claiming that all these gods, whatever their names, are really the one true Godde of Israel.
Jesus was the first one to suggest that Godde could be addressed intimately, just as much as a friend as the Ruler of the Universe. Jesus taught us to refer to Godde as "Abba," which is today's Hebrew means "Daddy." Because family life was vastly different then, "Abba" then was not quite as intimately familiar a word as "Daddy" is today; it was used more as a mark of respect, perhaps the way some British schooloys once called their fathers "Pater" or "the Governor." Jesus is inviting us to pray to Godde as he does himself, with the innocence and trustfulness of children.
What's in a name? In China, Coca-Cola is not a popular drink — because the sounds "coca cola" in Chinese mean "bite the wax tadpole." Mmm, delicious!